1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Clang Control Flow Integrity (CFI) type definitions.
*/
#ifndef _LINUX_CFI_TYPES_H
#define _LINUX_CFI_TYPES_H
#ifdef __ASSEMBLY__
#include <linux/linkage.h>
#ifdef CONFIG_CFI_CLANG
/*
* Use the __kcfi_typeid_<function> type identifier symbol to
* annotate indirectly called assembly functions. The compiler emits
* these symbols for all address-taken function declarations in C
* code.
*/
#ifndef __CFI_TYPE
#define __CFI_TYPE(name) \
.4byte __kcfi_typeid_##name
#endif
#define SYM_TYPED_ENTRY(name, linkage, align...) \
linkage(name) ASM_NL \
align ASM_NL \
__CFI_TYPE(name) ASM_NL \
name:
#define SYM_TYPED_START(name, linkage, align...) \
SYM_TYPED_ENTRY(name, linkage, align)
#else /* CONFIG_CFI_CLANG */
#define SYM_TYPED_START(name, linkage, align...) \
SYM_START(name, linkage, align)
#endif /* CONFIG_CFI_CLANG */
#ifndef SYM_TYPED_FUNC_START
#define SYM_TYPED_FUNC_START(name) \
SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)
#endif
#else /* __ASSEMBLY__ */
#ifdef CONFIG_CFI_CLANG
#define DEFINE_CFI_TYPE(name, func) \
/* \
* Force a reference to the function so the compiler generates \
* __kcfi_typeid_<func>. \
*/ \
__ADDRESSABLE(func); \
/* u32 name __ro_after_init = __kcfi_typeid_<func> */ \
extern u32 name; \
asm ( \
" .pushsection .data..ro_after_init,\"aw\",\%progbits \n" \
" .type " #name ",\%object \n" \
" .globl " #name " \n" \
" .p2align 2, 0x0 \n" \
#name ": \n" \
" .4byte __kcfi_typeid_" #func " \n" \
" .size " #name ", 4 \n" \
" .popsection \n" \
);
#endif
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_CFI_TYPES_H */
|
